Firm standardization and overtime work: evidence from satellite nighttime light data in China

Overtime work is a widespread labour phenomenon in developing countries, and curbing overtime work remains a persistent global challenge. Using A-share listed companies from 2012 to 2024 as the research sample, this paper examines the relationship between firm standardization and overtime work. Satellite-based night-time light data are used to measure firms’ overtime work levels. The empirical results show that firm standardization significantly reduces overtime work within firms. Mechanism analyses indicate that firm standardization mitigates overtime work by improving production efficiency and increasing the extent of production outsourcing. Heterogeneity analysis reveals that this effect is more pronounced in industries with lower competition, in labour-intensive firms, and among non-state-owned firms. However, further analyses provide suggestive evidence of a potential supply-chain transfer effect of overtime work. While firm standardization reduces overtime within focal firms, it may be associated with higher overtime among upstream suppliers through the forcing effect of downstream efficiency gains and the transfer effect of production outsourcing. This study provides new insights into curbing overtime culture in developing countries and highlights that organizational improvements within firms may be accompanied by unintended labour burdens elsewhere in the supply chain, offering new empirical evidence on the broader economic consequences of firm standardization.